Model B Crankshaft

Other than the obvious (journal/rod diameters) the only other issue I've heard of is a tendency of the rods to hit against the sides of the crankcase. I believe the B block is relieved a bit for clearance at this place.

It is possible to compensate for this.

I explored the option but have yet to act on it.

Joe K
 
The main beartings will need to be cut down to model A size. You will need model B or aftermarket special connecting rods. If model B rods are used, special rod nuts will be needed or the oil pan will need some minor mods to clear.
 
Purdy Swoft said:
The main beartings will need to be cut down to model A size. You will need model B or aftermarket special connecting rods. If model B rods are used, special rod nuts will be needed or the oil pan will need some minor mods to clear.
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The minor mods of the oil pan are extremely minor. Bolt the pan in place and turn over the engine. A rod will hit the pan. Remove the pan and with a ball peen hammer install some clearance for the rod. You will have to R&R the pan at least 8 times to get all you locations marked. Not rocket science. :D
 
daveymc29 said:
Thanks, it all sounds rather simple, just time consuming and a few bucks for the machining.
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Hey davey,
The rods will clear block, but will touch pan..ergo pan dimples, as said. You will have the benefit of larger/stronger rod journals and use any B crank that you wish to do this, i.e.- Ford first edition..without counterweights, right up thru C crank.

If I were you, I'd get a copy of member Jim Brierley's book and you will not only have answers to the instant inquiry....but much/much more, IMO :) ! And, if you do not comprehend what you are reading (my problem,eh :p !), you can contact Jim B to clarify such. He (Mr. F.A.S.T.) is easy to talk to and most knowledgeable !
 
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The beaver tail crankshaft isn't a mobel B crankshaft. The beaver tail crankshaft was used in 1928 and has the same journal sizes as the later model A crankshaft
 
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daveymc29,

I recently did this. Had the mains ground to standard A size and used Snyders B rods which had nuts that did not contact the sump. Also fitted a modern rear seal which I hope will not leak too much. I expect to run this engine in the next month or so.

Cheers,
Gavin
 
The oil slinger is a different size and needs to be machined to fit the A block if it is off by just a few thou diameter, thickness and taper it will leak
find a machine shop that has done this
or you have you have it machined for a modern seal easier
 
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